1. Field of the Invention
This invention relates to the recording of three-dimensional (3D) images from remote distances, in general for remote surveillance. The invention could, for example, also be used for weather, mapping, tracking ocean currents, seismic surveys or aircraft flight control. It is applicable, in real time, throughout the electro-magnetic spectrum particularly in the visible, infra-red and microwave portions. It may also be used for sonar. Steps in this present invention relate to preparing these images for transmission and display.
2. Description of the Related Art
Most remote tracking, photography or surveillance is done with two-dimensional (2D) recording devices. Separately formed images are recorded and stitched (often much later) to form mosaics of landscapes or geologic formations. Google earth is a good example of mosaic formations. The boundaries of the mosaic sections are very visible with stitch lines. Adjacent frames appear to be taken at different times of day under different weather conditions. Although it may be possible to form stereo pairs from some of these images, it would be done only on a case-by-case basis using huge computing resources.
Synthetic apertures have been long used in aircraft with side-looking radar for taking sequential images of terrain. These images may be stitched and merged to give 2D radar terrain maps. This is almost always done at a later time with ground-based computers. Similarly, synthetic apertures may be used for visual images, with the photos stitched to give 2D panoramas. These photos may be stitched digitally within the cameras. However, this takes time even for 2D, and then only produces still photos
The creation of motion 3D is, in comparison, highly complex (See, for example, Avatar). Until the recent arrival of very high-speed chips the complications of transitioning from 2D to 3D stills have been great, and from there to 3D video much greater again.
However, we are now at the point where, with high-speed chips, this can be done. With elegant algorithms we can, in the present invention, now provide imaging methods for acquiring 3D remotely which is as good as being in the presence of the subject observed—be it a person, a building, a football field or a battlefield. With the methods proposed in the present invention we can provide 3D surveillance in very close to real-time, delays of a few seconds being due almost solely to the motion of the camera between sequential images.
In the present invention the irregularities of motion are smoothed out to give virtually real-time 3D video from remote locations, from moving vehicles such as aircraft, and from satellites.